What Are Cider Co-Ferments?

All hard cider is, by definition, fermented. But what does it mean when a cider is described or labeled as a “co-ferment”? Perhaps you’ve been seeing this word more often lately — we can definitely confirm (anecdotally) that there are more and more ciders and wines out there in this style!

To get the scoop on the ins and outs of co-ferments, we checked in with Kim Hamblin, the co-founder of Art + Science, an Oregon-based producer of natural cider, perry and wine. Using foraged, organic and biodynamic fruit, Kim and her partner Dan have been experimenting with co-ferments for years!

The simple and straightforward definition of a co-ferment is the result of two or more ingredients that ferment together, simultaneously. For instance, Art + Science makes a product called Symbiosis (which has been around since 2015) that is a co-ferment of apples and grapes.


Art + Science Symbiosis

“To make Symbiosis, we press all the apples and throw the juice in with whole grapes that aren’t pressed, and ferment that all together for about three weeks,” Kim says.

She notes that co-ferments can be made with all kinds of fruit beyond apples and grapes, including plums, berries, cherries and pears. It can even mean different kinds of apples all fermented together! The co-ferment might be the juice of multiple ingredients in a tank together, or whole grapes with apple or pear juice. As with so many decisions in the cellars, sometimes it just comes down to what’s easier to manage.

“It’s a lot easier to take whole grapes and ferment them with apple or pear juice than it is to ferment apple mash with grape juice. That is so sloppy to press!”

cider co-ferment

foraged co-ferment ingredients from Art + Science

For Art + Science, the decision to start making co-ferments arose out of circumstance. In 2015, Dan was working at a winery that had excess Grüner Veltliner grapes that Kim and Dan purchased.

“We’d just started using apples in our products, but there weren’t a lot of cider apples available yet for purchasing,” she remembers. “It’s hard to forage apples with good tannin and what Dan liked about Grüner, it that it has some good tannins. He thought to take these foraged apples and blend them with the Grüner to give them that edge.”

This process of making a cider (or cider/wine hybrid, as it were) is different than, say, a cider that’s fully fermented and then rested on grape skins, which is a method used to make some rosé ciders. When asked why cidermakers might choose a co-ferment instead of a blend, Kim suggests a few reasons. One is about developing deeper, more intense flavors in fruit that, on its own, might not be that exciting.

“I don’t think we’d do co-ferments with cider-specific apples, but say we have a bunch of apples that we picked from an abandoned dessert apple orchard,” she notes. “They might taste alright, but they’re not really great cider apples — the flavor isn’t as structured and there’s not a ton of interest to it. They need more body and more flavors and we can use co-fermentation to make it more interesting.”

Art + Science FruitNat, a co-ferment of pear, apple, Mondeuse Noir grapes and plums

Another reason for making co-ferments that Kim references is being adaptable and creative with what you’ve got to work with as a cidermaker. For smaller producers, what fruit they’re able to procure each year might vary wildly depending on weather, growing conditions and if it’s a prolific or challenging harvest year.

“Sometimes what we’re doing is just based on what fruit we get,” she says. “Like last year we got all these plums, so we did a plum/Grüner co-ferment and that’s really wild. This year, there’s a lack of apples and no plums, so we’ll have to do something a little different.”

She also notes that for some wineries and cideries, it may be a response to losing grapes due to smoke taint from wildfires.

“Since 2020, it seems like a lot of wineries started jumping into co-ferments, maybe as a way to bury a bit of smoke taint in the apples, or just because a lot of them had less fruit.”

But for Art + Science, she says, it’s really about the joy of experimentation.

“Fermenting things separately, you know what their characteristics are, but with co-ferments you don’t really know,” she says. “Sometimes it’s a happy accident. We throw caution to the wind with a lot of our fermentations, and don’t try to predict how they’ll turn out. We’re probably a little different than most wineries in that respect!”

Curious about co-ferments? Here are a few others to check out:

Have you tried any co-fermented ciders? What are some of your favs? We want to know!

  • Bottle shots: Northwest Cider Club
  • All other photos: Art + Science